Embodiments of the present technology generally relate to voltage regulator-alternator configurations. More particularly, embodiments of the present technology relate to voltage regulator-alternator configurations that distribute loads among a plurality of alternators, and fail-safe mechanisms used in connection with such voltage regulator-alternator configurations.
An alternator is an electromechanical device that converts mechanical energy to electrical energy. Alternators are used, for example, to convert mechanical energy supplied from the engine of an automobile to electrical energy. The electrical energy that is created can then be stored in a battery and/or consumed. Alternators can be used to convert mechanical energy supplied from other sources to electrical energy.
A voltage regulator is an electrical regulator that controls the voltage generated by an alternator. In general, a voltage regulator detects the voltage output by an alternator and comprises that voltage to a reference voltage. If the voltage being output by the alternator is higher than the reference voltage, the voltage regulator can instruct the alternator to reduce its voltage output. Likewise, if the voltage being output by the alternator is lower than the reference voltage, the voltage regulator can instruct the alternator to increase its voltage output.
In some systems, more electrical energy is required than can be converted/supplied, or than is desirable to convert/supply, using a single alternator. Such systems can utilize a plurality of alternators to convert/supply electrical energy. Also, systems that utilize a plurality of alternators can also utilize a plurality of voltage regulators.
In systems that utilize a plurality of alternators, various voltage regulator-alternator configurations have been used to control the voltage generated by the alternators. With regard to such systems, it is recognized that it is preferable to distribute the load among alternators such that no single alternator is supplying too much or too little of the required electrical energy.
However, as described in the Background Of The Invention section of U.S. Pat. No. 5,723,972 entitled Fail-Safe Common Control Of Multiple Alternators Electrically Connected In Tandem Parallel For Producing High Current, which issued on Mar. 3, 1998, the voltage regulator-alternator configurations known in the art have drawbacks.
Further, there are also drawbacks regarding the voltage regulator-alternator configuration described in the Abstract of U.S. Pat. No. 5,723,972 as: “One electronic voltage regulator that is modified to become a designated master produces a ‘universal’ control signal in response to variations in a voltage across the battery/load. This ‘universal’ control signal is further used in the master electronic voltage regulator itself to develop a conventional signal providing regulation to an associated alternator. The same universal control signal is provided by wired connection to all remaining, preferably identical, voltage regulators, each of which is modified to become a follower voltage regulator. Each of the follower voltage regulators produces a signal for the regulation control of its associated alternator not by reference to the battery/load voltage (as would be normal), but rather by reference to the universal control signal.”
One drawback of the voltage regulator-alternator configuration described in U.S. Pat. No. 5,723,972, is that the system requires one “master” voltage regulator used in connection with “follower” voltage regulators. In the system, the “master” voltage regulator is the only control device and, thus, if the master voltage regulator fails, the entire electrical system can shut down or try to run away, which means that the electrical system could continue to create electrical energy without being regulated, for example, by a voltage regulator. Further, “master” voltage regulators and “follower” voltage regulators are distinct in design and function and, thus, “master” voltage regulators and “follower” voltage regulators are not interchangeable, which can decrease convenience.
Thus, there is a need for new voltage regulator-alternator configurations that distribute loads among a plurality of alternators without relying on a single control device, and without multiple voltage regulators that are distinct in design and function. Further, as with any electrical system, in order to prevent damage and/or undesirable conditions, there is a need for fail-safe mechanisms to be used in connection with new voltage regulator-alternator configurations.